How to restore cloth presets?
To restore default settings of presets choose them again from the dropdown list (this can be done not only for cloth presets, but for other presets as well). Note that any already made changes will be lost.



This won't work if you changed any preset settings and then saved your User Preferences; new settings will overwrite default ones.          Note that preferences were separated from startup file.


If attempting to restore cloth preset after its deletion most likely you will need to install Blender once more (if you haven't saved backup of .py files with settings before deleting them) because file is being deleted as you press 'minus' button.